From 451f4d875537c073a966d6ccfb2fe08a497fbd7b Mon Sep 17 00:00:00 2001
From: Michael Jeanson <mjeanson@efficios.com>
Date: Wed, 15 Jun 2016 11:01:08 -0500
Subject: [PATCH] Set thread stack size to ulimit soft value

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
[Philippe: grabbed from the mailing list:
    https://lists.lttng.org/pipermail/lttng-dev/2016-June/026196.html
]
Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
---
 src/bin/lttng-consumerd/lttng-consumerd.c | 17 ++++++----
 src/bin/lttng-relayd/live.c               | 10 +++---
 src/bin/lttng-relayd/live.h               |  2 +-
 src/bin/lttng-relayd/main.c               | 14 +++++---
 src/bin/lttng-sessiond/main.c             | 27 +++++++++------
 src/common/utils.c                        | 56 +++++++++++++++++++++++++++++++
 src/common/utils.h                        |  1 +
 7 files changed, 99 insertions(+), 28 deletions(-)

diff --git a/src/bin/lttng-consumerd/lttng-consumerd.c b/src/bin/lttng-consumerd/lttng-consumerd.c
index 00660fc..2f1d01c 100644
--- a/src/bin/lttng-consumerd/lttng-consumerd.c
+++ b/src/bin/lttng-consumerd/lttng-consumerd.c
@@ -57,6 +57,8 @@
 static pthread_t channel_thread, data_thread, metadata_thread,
 		sessiond_thread, metadata_timer_thread, health_thread;
 
+static pthread_attr_t *tattr;
+
 /* to count the number of times the user pressed ctrl+c */
 static int sigintcount = 0;
 
@@ -351,6 +353,9 @@ int main(int argc, char **argv)
 		}
 	}
 
+	/* Get stacksize limit */
+	tattr = get_pthread_attr_stacksize();
+
 	/*
 	 * Starting from here, we can create threads. This needs to be after
 	 * lttng_daemonize due to RCU.
@@ -498,7 +503,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage the client socket */
-	ret = pthread_create(&health_thread, NULL,
+	ret = pthread_create(&health_thread, tattr,
 			thread_manage_health, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -517,7 +522,7 @@ int main(int argc, char **argv)
 	cmm_smp_mb();	/* Read ready before following operations */
 
 	/* Create thread to manage channels */
-	ret = pthread_create(&channel_thread, NULL,
+	ret = pthread_create(&channel_thread, tattr,
 			consumer_thread_channel_poll,
 			(void *) ctx);
 	if (ret) {
@@ -528,7 +533,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage the polling/writing of trace metadata */
-	ret = pthread_create(&metadata_thread, NULL,
+	ret = pthread_create(&metadata_thread, tattr,
 			consumer_thread_metadata_poll,
 			(void *) ctx);
 	if (ret) {
@@ -539,7 +544,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage the polling/writing of trace data */
-	ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
+	ret = pthread_create(&data_thread, tattr, consumer_thread_data_poll,
 			(void *) ctx);
 	if (ret) {
 		errno = ret;
@@ -549,7 +554,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create the thread to manage the receive of fd */
-	ret = pthread_create(&sessiond_thread, NULL,
+	ret = pthread_create(&sessiond_thread, tattr,
 			consumer_thread_sessiond_poll,
 			(void *) ctx);
 	if (ret) {
@@ -563,7 +568,7 @@ int main(int argc, char **argv)
 	 * Create the thread to manage the UST metadata periodic timer and
 	 * live timer.
 	 */
-	ret = pthread_create(&metadata_timer_thread, NULL,
+	ret = pthread_create(&metadata_timer_thread, tattr,
 			consumer_timer_thread, (void *) ctx);
 	if (ret) {
 		errno = ret;
diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index e2096ec..32efab1 100644
--- a/src/bin/lttng-relayd/live.c
+++ b/src/bin/lttng-relayd/live.c
@@ -2147,13 +2147,13 @@ int relayd_live_join(void)
 /*
  * main
  */
-int relayd_live_create(struct lttng_uri *uri)
+int relayd_live_create(struct lttng_uri *uri, const pthread_attr_t *tattr)
 {
 	int ret = 0, retval = 0;
 	void *status;
 	int is_root;
 
-	if (!uri) {
+	if (!uri || !tattr) {
 		retval = -1;
 		goto exit_init_data;
 	}
@@ -2186,7 +2186,7 @@ int relayd_live_create(struct lttng_uri *uri)
 	}
 
 	/* Setup the dispatcher thread */
-	ret = pthread_create(&live_dispatcher_thread, NULL,
+	ret = pthread_create(&live_dispatcher_thread, tattr,
 			thread_dispatcher, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -2196,7 +2196,7 @@ int relayd_live_create(struct lttng_uri *uri)
 	}
 
 	/* Setup the worker thread */
-	ret = pthread_create(&live_worker_thread, NULL,
+	ret = pthread_create(&live_worker_thread, tattr,
 			thread_worker, NULL);
 	if (ret) {
 		errno = ret;
@@ -2206,7 +2206,7 @@ int relayd_live_create(struct lttng_uri *uri)
 	}
 
 	/* Setup the listener thread */
-	ret = pthread_create(&live_listener_thread, NULL,
+	ret = pthread_create(&live_listener_thread, tattr,
 			thread_listener, (void *) NULL);
 	if (ret) {
 		errno = ret;
diff --git a/src/bin/lttng-relayd/live.h b/src/bin/lttng-relayd/live.h
index 2b8a3a0..6cd85e9 100644
--- a/src/bin/lttng-relayd/live.h
+++ b/src/bin/lttng-relayd/live.h
@@ -24,7 +24,7 @@
 
 #include "lttng-relayd.h"
 
-int relayd_live_create(struct lttng_uri *live_uri);
+int relayd_live_create(struct lttng_uri *live_uri, const pthread_attr_t *tattr);
 int relayd_live_stop(void);
 int relayd_live_join(void);
 
diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index 6ad6566..505e884 100644
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -119,6 +119,8 @@ static pthread_t dispatcher_thread;
 static pthread_t worker_thread;
 static pthread_t health_thread;
 
+static pthread_attr_t *tattr;
+
 /*
  * last_relay_stream_id_lock protects last_relay_stream_id increment
  * atomicity on 32-bit architectures.
@@ -2778,6 +2780,8 @@ int main(int argc, char **argv)
 		}
 	}
 
+	/* Get stack size limit */
+	tattr = get_pthread_attr_stacksize();
 
 	/* Initialize thread health monitoring */
 	health_relayd = health_app_create(NR_HEALTH_RELAYD_TYPES);
@@ -2840,7 +2844,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage the client socket */
-	ret = pthread_create(&health_thread, NULL,
+	ret = pthread_create(&health_thread, tattr,
 			thread_manage_health, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -2850,7 +2854,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Setup the dispatcher thread */
-	ret = pthread_create(&dispatcher_thread, NULL,
+	ret = pthread_create(&dispatcher_thread, tattr,
 			relay_thread_dispatcher, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -2860,7 +2864,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Setup the worker thread */
-	ret = pthread_create(&worker_thread, NULL,
+	ret = pthread_create(&worker_thread, tattr,
 			relay_thread_worker, NULL);
 	if (ret) {
 		errno = ret;
@@ -2870,7 +2874,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Setup the listener thread */
-	ret = pthread_create(&listener_thread, NULL,
+	ret = pthread_create(&listener_thread, tattr,
 			relay_thread_listener, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -2879,7 +2883,7 @@ int main(int argc, char **argv)
 		goto exit_listener_thread;
 	}
 
-	ret = relayd_live_create(live_uri);
+	ret = relayd_live_create(live_uri, tattr);
 	if (ret) {
 		ERR("Starting live viewer threads");
 		retval = -1;
diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index c8e4e53..b8f1bde 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -212,6 +212,8 @@ static pthread_t ht_cleanup_thread;
 static pthread_t agent_reg_thread;
 static pthread_t load_session_thread;
 
+static pthread_attr_t *tattr;
+
 /*
  * UST registration command queue. This queue is tied with a futex and uses a N
  * wakers / 1 waiter implemented and detailed in futex.c/.h
@@ -2402,7 +2404,7 @@ static int spawn_consumer_thread(struct consumer_data *consumer_data)
 		goto error;
 	}
 
-	ret = pthread_create(&consumer_data->thread, NULL, thread_manage_consumer,
+	ret = pthread_create(&consumer_data->thread, tattr, thread_manage_consumer,
 			consumer_data);
 	if (ret) {
 		errno = ret;
@@ -5638,6 +5640,9 @@ int main(int argc, char **argv)
 		goto exit_create_run_as_worker_cleanup;
 	}
 
+	/* Get stack size limit */
+	tattr = get_pthread_attr_stacksize();
+
 	/*
 	 * Starting from here, we can create threads. This needs to be after
 	 * lttng_daemonize due to RCU.
@@ -5672,7 +5677,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to clean up RCU hash tables */
-	ret = pthread_create(&ht_cleanup_thread, NULL,
+	ret = pthread_create(&ht_cleanup_thread, tattr,
 			thread_ht_cleanup, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6044,7 +6049,7 @@ int main(int argc, char **argv)
 	load_info->path = opt_load_session_path;
 
 	/* Create health-check thread */
-	ret = pthread_create(&health_thread, NULL,
+	ret = pthread_create(&health_thread, tattr,
 			thread_manage_health, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6054,7 +6059,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage the client socket */
-	ret = pthread_create(&client_thread, NULL,
+	ret = pthread_create(&client_thread, tattr,
 			thread_manage_clients, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6064,7 +6069,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to dispatch registration */
-	ret = pthread_create(&dispatch_thread, NULL,
+	ret = pthread_create(&dispatch_thread, tattr,
 			thread_dispatch_ust_registration, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6074,7 +6079,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage application registration. */
-	ret = pthread_create(&reg_apps_thread, NULL,
+	ret = pthread_create(&reg_apps_thread, tattr,
 			thread_registration_apps, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6084,7 +6089,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage application socket */
-	ret = pthread_create(&apps_thread, NULL,
+	ret = pthread_create(&apps_thread, tattr,
 			thread_manage_apps, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6094,7 +6099,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create thread to manage application notify socket */
-	ret = pthread_create(&apps_notify_thread, NULL,
+	ret = pthread_create(&apps_notify_thread, tattr,
 			ust_thread_manage_notify, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6104,7 +6109,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create agent registration thread. */
-	ret = pthread_create(&agent_reg_thread, NULL,
+	ret = pthread_create(&agent_reg_thread, tattr,
 			agent_thread_manage_registration, (void *) NULL);
 	if (ret) {
 		errno = ret;
@@ -6116,7 +6121,7 @@ int main(int argc, char **argv)
 	/* Don't start this thread if kernel tracing is not requested nor root */
 	if (is_root && !opt_no_kernel) {
 		/* Create kernel thread to manage kernel event */
-		ret = pthread_create(&kernel_thread, NULL,
+		ret = pthread_create(&kernel_thread, tattr,
 				thread_manage_kernel, (void *) NULL);
 		if (ret) {
 			errno = ret;
@@ -6127,7 +6132,7 @@ int main(int argc, char **argv)
 	}
 
 	/* Create session loading thread. */
-	ret = pthread_create(&load_session_thread, NULL, thread_load_session,
+	ret = pthread_create(&load_session_thread, tattr, thread_load_session,
 			load_info);
 	if (ret) {
 		errno = ret;
diff --git a/src/common/utils.c b/src/common/utils.c
index 1e52ae0..593d6cc 100644
--- a/src/common/utils.c
+++ b/src/common/utils.c
@@ -31,6 +31,8 @@
 #include <pwd.h>
 #include <sys/file.h>
 #include <unistd.h>
+#include <stdbool.h>
+#include <sys/resource.h>
 
 #include <common/common.h>
 #include <common/runas.h>
@@ -1383,3 +1385,57 @@ int utils_show_man_page(int section, const char *page_name)
 		section_string, page_name, NULL);
 	return ret;
 }
+
+static bool pthread_ss_done = false;
+static pthread_attr_t *tattr = NULL;
+static pthread_attr_t tattr_value;
+
+LTTNG_HIDDEN
+pthread_attr_t *get_pthread_attr_stacksize() {
+	int ret = 0;
+	size_t ptstacksize;
+	struct rlimit rlim;
+
+	/* Return cached value */
+	if (pthread_ss_done) {
+		goto end;
+	}
+
+	/* Get stack size limits */
+	ret = getrlimit(RLIMIT_STACK, &rlim);
+	if (ret < 0) {
+		PERROR("getrlimit");
+		goto end;
+	}
+	DBG("Stack size limits: soft %lld, hard %lld bytes",
+			(long long) rlim.rlim_cur,
+			(long long) rlim.rlim_max);
+
+	/* Get default thread stack size */
+	ret = pthread_attr_getstacksize(&tattr_value, &ptstacksize);
+	if (ret < 0) {
+		PERROR("pthread_attr_getstacksize");
+		goto end;
+	}
+	DBG("Default pthread stack size is %zu bytes", ptstacksize);
+
+	/* Check if default thread stack size respects ulimits */
+	if (ptstacksize < rlim.rlim_cur) {
+		DBG("Your libc doesn't honor stack size limits, setting thread stack size to soft limit (%lld bytes)", (long long) rlim.rlim_cur);
+
+		/* Create pthread_attr_t struct with ulimit stack size */
+		ret = pthread_attr_setstacksize(&tattr_value, rlim.rlim_cur);
+		if (ret < 0) {
+			PERROR("pthread_attr_setstacksize");
+			goto end;
+		}
+
+		/* Set pointer */
+		tattr = &tattr_value;
+	}
+
+	/* Enable cached value */
+	pthread_ss_done = true;
+end:
+	return tattr;
+}
diff --git a/src/common/utils.h b/src/common/utils.h
index 7285f5c..568c123 100644
--- a/src/common/utils.h
+++ b/src/common/utils.h
@@ -60,5 +60,6 @@ int utils_create_lock_file(const char *filepath);
 int utils_recursive_rmdir(const char *path);
 int utils_truncate_stream_file(int fd, off_t length);
 int utils_show_man_page(int section, const char *page_name);
+pthread_attr_t *get_pthread_attr_stacksize();
 
 #endif /* _COMMON_UTILS_H */
-- 
2.7.4

